module-admin-order-columns/etc/adminhtml/di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\Sales\Block\Adminhtml\Order\View\Items\Renderer\DefaultRenderer">
        <plugin name="shopkeeper_admin_order_columns_renderer"
                type="Shopkeeper\AdminOrderColumns\Plugin\Order\View\Items\Renderer\DefaultRenderer"
                sortOrder="10"/>
    </type>
    <type name="Magento\Sales\Block\Adminhtml\Order\View\Items">
        <plugin name="shopkeeper_admin_order_columns"
                type="Shopkeeper\AdminOrderColumns\Plugin\Order\View\ItemsColumns"
                sortOrder="10"/>
    </type>
</config>